Monday, May 11, 2009

"Knowing For Sure"

I seemed to be interested in how we know things.

There’s a name for that inquiry – epistemology – which, according to my dictionary, is “a branch of philosophy that investigates the origin, nature, methods, and limits of human knowledge.” People have been curious about how we know things for some time, going at least as far back as Aristotle.

Pursuing this interest, I sign up for a philosophy class at UCLA Extension. Skepticism and Rationality. And you know what? It turns out that wasn’t exactly what I was interested in. The class offered varying theories on the mechanical process of how we know things, which while interesting to a point was not quite the itch that I was looking to scratch.

Taking that wrong turn, however, helped me discover what I was really interested in, which was not how we know things, but something slightly different. That being:

How do we know what we know is true?

We are told a lot of things in our lives. By our parents, our peers, some expert says, “Believe this!” But that’s just stuff. Stuff that comes at us and we take it in, and we store it away. The question is, how do we know for sure whether any of that stuff we took in and stored away, and started thinking of as the truth, and after a while it became the truth, out of habit if for no other reason, how do know if any of that stuff

Is actually true?

I remember precisely when my interest in this subject kicked into gear. I was sitting at home, perusing TV Guide, my reading matter of choice for, maybe, my life, till they went to the larger format, at which point it started looking too much like Us Weekly and I quit.

I was about thirty, and had just gotten contact lenses for the first time. Before that, I wore thick bifocals, the residue of some cataract surgery, which I’d undergone when I was two. (Imagine that. A two year-old exposed to the shocking brightness of an Operating Room. That’s probably why I flinch when they turn on the lights at ballgames.)

When you get contacts, you’re supposed to gradually build up the “wearing time.” For the first week or so, you keep them in a few hours, then you take them out and switch back to your glasses. One day, when I hit the “switching point”, I happened to be leafing through TV Guide, maybe wrestling with the Crossword Puzzle. Following instructions, I removed my contacts, put on my bifocals, and returned to my TV Guide.

That’s when I noticed it.

For me, it was an insight rivaling Archimedes’ discovery of displacement when he overflowed his bathtub, though it required a lot fewer towels to clean up.

What had jumped to my attention was this:

When I was reading TV Guide wearing my contacts, the letters printed in the magazine were one size. But when I switched to my bifocals and went back to the TV Guide, I immediately discovered that the letters in the magazine had become


And I mean all of them.

I remember thinking at that moment,

“What the heck is going on?”

The letters themselves couldn’t have changed.

“Let’s all get smaller!”

Letters can’t do that.

I’m pretty sure nobody’d sneaked into my apartment while I was in the bathroom taking out my contacts, and, as a prank, replaced my TV Guide with the exact same issue but with littler print.

My eyesight hadn’t gotten worse in the intervening thirty seconds.

So what exactly had transpired?

(I was also intrigued by what size the letters in that TV Guide actually were? And more interesting still, did everybody who looked at them see them a little bit differently?)

If you’re older than, say, eight, there is probably no mystery in my “epiphany.” The size of the print in my TV Guide appeared to be altered due to a small but noticeable discrepancy between my bifocal prescription (slightly less powerful) and the prescription for my contact lenses. I’m no dummy. I was pretty much on to that right away. Though I do admit to some momentary bafflement.

My experience shook me up, bringing into question, in every arena, from sensory information to strongly held beliefs, the uncertain issue of certainty.

I mean, hey,

How do I know what I know is true

When I personally

Just saw the same thing

Two different ways?


A. Buck Short said...

I believe conservatives lambast this phenomenon as "optical relativism." Personally I take all my epistemological direction from Doug Henning.

bbot said...

Bayesian rationalists get really tetchy when you use the word "certain". Or in probability speak, something with a likelihood of 1.0. (100% likelihood)

Not the least, this is because it is impossible to achieve a posterior probability of 1.0, and also because it means that you are so confident in your certainty that there is no contrary evidence that can convince you otherwise.

If you believe x with a probability of 1; and the clouds rolled back and the voice of God thundered forth, saying, "Actually, x is false," then you would have to reply with, "Screw you, God. I am certain."

On the topic of epistemology, have a blog post concerning inferental distances or why scientists always start heaving great sighs when reporters ask them to explain their work, and keep it simple this time, egghead.

growingupartists said...

I like your Future of Humanity site, bbot. What's the difference then, between the future of humanity and the future of civilization. Link to post if that would be easier.

Shady Grove Eye Vision Care said...

Bifocals have an additional power on the bottom part of the lens to aid close focus in presbyopic people so they can see far and close with one lens.